Recovery of oil from shale



Patented Jan. 5, 1954 RECOVERY OF OIL FROM SHALE James K. Truitt, Wappingers Falls, and George B. Arnold, Glenham, N. Y., assignors to The Texas Company, New York, N. Y., a corporation of Delaware No Drawing. Application July 12, 1951, Serial No. 236,478

2 Claims. 1

This invention relates to the recovery of oil from oil shale and contemplates the digestion of lump shale with water under elevated temperatures and high pressures.

We have discovered that by digesting the shale with water under high temperatures and high super-atmospheric pressures the kerogen is resolved and displaced by the water. The temperature and pressure conditions to efiect resolution of the kerogen vary somewhat with the character of the shale, but in general pressures of the order of 3000 lbs. and temperatures approximating 700 F. are required to effect a substantially complete resolution of the kerogen and recovery of the oil content of the shale.

At temperatures around 500 F. and, pressures of about 1000 lbs. the water has little or no effect in resolving the kerogen but as the temperature is increased above 500 F. and as the pressure is increased above 1000 lbs, the effect of the water in resolving the kerogen becomes noticeable. The amount of oil recovered increases generally as the temperature or pressure is further increased, but pressures as high as about 3000 p. s. i. g. and temperatures at least approximating as high as 700 F. are required to effect a substantially complete recovery of the oil.

The effect of the temperature and pressure is well shown by a series of typical runs in which the oil shale was subjected to a variety of temperature-pressure conditions. The shale for these runs was crushed shale composed of material of which the largest sizes approximated A; of an inch and of smaller material including dust. The shale in each run was digested with approximately equal weight of water in a closed bomb for a period of six hours. The following table gives the temperature-pressure conditions and the recoveries of oil obtained in these particular runs:

It will be seen that while material oil recoveries were obtained under the lower temperaturepressure conditions that only run 1, which was under the most severe conditions of temperature and pressure, accomplished a sufliciently high yield of recovered oil to be considered suitable for commercial operations. In determining the data for the carbon contained in the solid residue the treated shale was extracted with benzene and then dried.

The treatment with the water reduces the shale to a soft clay consistency. It is preferable to have the shale crushed to relatively small sizes.

in order to facilitate complete penetration and displacement by the water. In our process crushed shale containing maximum sizes of about 1 or 2 inches has been successfully processed with digestion periods not exceeding about six hours.

Although a preferred embodiment of the invention has been described herein, it will be understood that various changes and modifications may be made therein, while securing to a greater or less extent some or all of the benefits of the invention, without departing from the spirit and scope thereof.

We claim:

1. The method of recovering oil from oil shale containing kerogen that comprises charging to a retort feed materials consisting of the shale and water in large amount approximating the weight of the shale and subjecting the material in the retort to a temperature in excess of 500 F. under a pressure in excess of 1000 lbs. per square inch to thereby effect the decomposition of the kerogen and resultant formation of oil.

2. The method of recovering oil from oil shale containing kerogen that comprises charging to a retort feed materials consisting of the shale and water in large amount approximating the weight of the shale and subjecting the material in the retort to a temperature of the order of 700 F. under a pressure of the order of 3000 lbs. per square inch to thereby effect the decomposition of the kerogen and resultant formation of oil.

JAMES K. TRUITT. GEORGE E. ARNOLD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,486,243 I-Iackstaff Mar. 11, 1924 1,497,607 Streppel June 10, 1924 1,520,752 Horwitz Dec. 30, 1924 1,904,477 Krauch et a1. Apr. 18, 1933 1,936,819 Bayer Nov. 28, 1933 

1. THE METHOD OF RECOVERING OIL FROM OIL SHALE CONTAINING KEROGEN THAT COMPRISES CHARGING TO A RETORT FEED MATERIALS CONSISTING OF THE SHALE AND WATER IN LARGE AMOUNT APPROXIMATING THE WEIGHT OF THE SHALE AND SUBJECTING THE MATERIAL IN THE RETORT TO A TEMPERATURE IN EXCESS OF 500* F. UNDER A PRESSURE IN EXCESS OF 1000 LBS. PER SQUARE INCH TO THEREBY EFFECT THE DECOMPOSITION OF THE KEROGEN AND RESULTANT FORMATION OF OIL. 